Suction control arrangement for an open-end friction spinning machine

Abstract

An open end friction spinning machine is provided which exhibits a plurality of adjacently arranged spinning units, each spinning unit including two adjacently arranged rollers forming a wedge-shaped gap. Yarn formation takes place inside the wedge-shaped gap with the assistance of a friction effect of the rollers. This friction effect is dependent on the one hand on the outer surface structure of the rollers and on the other hand on the strength of the suction effect of a suction device creating a suction air stream in the wedge-shaped gap. It is provided that the outer surface structure of the rollers is examined so that a portion of the friction effect dependent upon the outer surface of the rollers can be determined. In order to maintain the entire friction effect in a predetermined range, the suction effect of the suction device can be adjusted corresponding to the measured value of the friction effect due to the outer surface of the rollers.

I claim: 
     
       1. An open-end friction spinning machine having at least one spinning unit including drivable friction surface means defining a yarn formation zone, suction air stream means adjacent the yarn formation zone for creating a suction effect in the yarn formation zone, said suction effect and said friction surface effect being capable of creating an overall friction effect in said yarn formation zone, comprising: surface friction effect examining means for determining said surface friction effect of said friction surface means, said surface friction effect examining means being capable of determining said surface friction effect without altering said friction surface means.   
     
     
       2. An open-end friction spinning machine according to claim 1, wherein said friction surface examining means comprises non-contact sensor means. 
     
     
       3. An open-end friction spinning machine according to claim 1, wherein said friction surface means comprises a pair of adjacently arranged friction rollers capable of being driven in the same rotational direction, and said yarn formation zone comprises a yarn-forming wedge-shaped gap formed between the pair of rollers. 
     
     
       4. An open-end friction spinning machine according to claim 2, wherein said non-contact sensor means comprises light sensing means. 
     
     
       5. An open-end friction spinning machine according to claim 1, comprising evaluation device means, said surface friction effect examining means being capable of generating signals corresponding to said surface friction effect, said evaluation device means being capable of receiving said signals. 
     
     
       6. An open-end friction spinning machine according to claim 1, comprising travelling maintenance device means, said surface friction effect examining means being disposed in said travelling maintenance device means. 
     
     
       7. An open-end friction spinning machine according to claim 5, comprising travelling maintenance device means, said evaluation device means being disposed in said travelling maintenance device means. 
     
     
       8. An open-end friction spinning machine according to claim 5, comprising travelling maintenance device means, said evaluation device means and said friction surface examining means being disposed in said travelling maintenance device means. 
     
     
       9. An open-end friction spinning machine according to claim 6, wherein said travelling maintenance device means includes adjusting means for adjusting said friction surface examining means relative to said friction surface means. 
     
     
       10. An open-end friction spinning machine according to claim 9, comprising friction surface drive control means for controlling the drive of said friction surface means. 
     
     
       11. An open-end friction spinning machine according to claim 5, comprising travelling maintenance device means, said maintenance device means including stopping means for stopping an examined spinning unit said stopping means being capable of being controlled by said evaluating device means. 
     
     
       12. An open-end friction spinning machine according to claim 5, comprising travelling maintenance device means, said maintenance device means including marking means for marking an examined spinning unit said marking means being capable of being controlled by said evaluating device means. 
     
     
       13. An open-end friction spinning machine according to claim 1, wherein said spinning unit includes suction effect adjusting means for adjusting the suction effect of the suction device means. 
     
     
       14. An open-end friction spinning machine according to claim 13, comprising travelling maintenance device means, said maintenance device means having controlling means for controlling said adjusting means, said controlling means being capable of controlling the suction effect at said spinning unit. 
     
     
       15. An open-end friction spinning machine according to claim 14, comprising evaluation device means, said surface friction effect examining means being capable of generating signals corresponding to said surface friction effect, said evaluation device means being capable of receiving said signals, said controlling means being responsive to said evaluation device means. 
     
     
       16. An open-end friction spinning machine according to claim 15, wherein said maintenance device means includes suction effect examining means for examining said suction effect, said suction effect examining means being capable of generating suction effect signals corresponding to said suction effect, said evaluation device means being capable of receiving said system effect signals. 
     
     
       17. An open-end friction spinning machine according to claim 1, comprising a plurality of spinning units.